End cover assembly, battery cell, battery, and electric apparatus

Abstract

An end cover assembly may include: a cover plate provided with an electrode lead-out hole; an electrode terminal located on one side of the cover plate in a thickness direction and covering the electrode lead-out hole; and a sealing element disposed between the electrode terminal and the cover plate so as to seal the electrode lead-out hole along a circumference of the electrode lead-out hole. The sealing element may include a body and a first insulating element. The first insulating element may be connected to the body and have a higher melting point than the body. The first insulating element may be configured to insulate the electrode terminal from the cover plate after the body is melted, so as to keep electrode terminals of two polarities insulated from each other at thermal runaway of a battery cell.

1 . An end cover assembly, comprising:
 a cover plate, provided with an electrode lead-out hole;   an electrode terminal, located on one side of the cover plate in a thickness direction and covering the electrode lead-out hole; and   a sealing element, disposed between the electrode terminal and the cover plate so as to seal the electrode lead-out hole along a circumference of the electrode lead-out hole, wherein the sealing element comprises a body and a first insulating element; the first insulating element is connected to the body and has a higher melting point than the body; and the first insulating element is configured to insulate the electrode terminal from the end cover after the body is melted.   
     
     
         2 . The end cover assembly according to  claim 1 , wherein the first insulating element is at least partially embedded into the body. 
     
     
         3 . The end cover assembly according to  claim 1 , wherein the body is in an annular shape, the first insulating element is provided in plurality, and the plurality of first insulating elements are spaced apart along a circumference of the body. 
     
     
         4 . The end cover assembly according to  claim 1 , wherein the body and the first insulating element are both annular and are both disposed around the electrode lead-out hole. 
     
     
         5 . The end cover assembly according to  claim 1 , wherein the body abuts against the electrode terminal and the cover plate. 
     
     
         6 . The end cover assembly according to  claim 1 , wherein the first insulating element is made of ceramic or silicon carbide, and the body is made of rubber. 
     
     
         7 . The end cover assembly according to  claim 1 , wherein the cover plate further comprises a flange; the flange surrounds the electrode lead-out hole and protrudes toward the electrode terminal in the thickness direction of the cover plate; and the first insulating element is located on a side of the flange farther away from the electrode lead-out hole. 
     
     
         8 . The end cover assembly according to  claim 7 , wherein a size of the first insulating element in the thickness direction of the cover plate is greater than a protrusion height of the flange. 
     
     
         9 . The end cover assembly according to  claim 7 , wherein the body comprises a first portion, a second portion and a third portion; the first portion is located on a side of the flange closer to the electrode lead-out hole; the second portion is located on a side of the flange farther away from the electrode lead-out hole; the third portion is located on a side of the flange closer to the electrode terminal; the third portion is connected to the first portion and the second portion; and the first insulating element is at least partially embedded into the second portion. 
     
     
         10 . The end cover assembly according to  claim 1 , wherein an insulating layer is formed on a circumferential surface of the electrode terminal, and the insulating layer has a higher melting point than the body. 
     
     
         11 . The end cover assembly according to  claim 10 , wherein the insulating layer is a rigid anodization layer. 
     
     
         12 . The end cover assembly according to  claim 1 , wherein the end cover assembly further comprises:
 a second insulating element, surrounding at least part of the circumferential surface of the electrode terminal and connected to the electrode terminal; and   a fixing element, fixed to the cover plate and connected to the second insulating element; wherein   the electrode terminal is fixed to the cover plate via the second insulating element and the fixing element; and the electrode terminal is insulated from the fixing element by the second insulating element.   
     
     
         13 . A battery cell, comprising:
 a housing with an opening;   an electrode assembly, disposed inside the housing; and   the end cover assembly according to  claim 1 , wherein the end cover assembly covers the opening, so as to seal the electrode assembly inside the housing.   
     
     
         14 . A battery, comprising the battery cell according to  claim 13 . 
     
     
         15 . An electric apparatus, comprising the battery according to  claim 14 .